SP6656EB Datasheet, PDF (2/4 Pages) Sipex Corporation – Evaluation Board Manual

1) Powering up the SP6656 Circuit
The SP6656 Evaluation Board can be powered from a single Li-Ion battery or a +2.7 to
+5.0V power supply. Connect with short leads directly to the “Vin” and “Gnd” posts.
Note the SP6656 will remain in “shutdown” until the EN Jumper J1 is applied to the Vin
or position 1 to 2.
2) VOUT PROGRAMMING
The SP6656 has a dynamically programmable output voltage using the OVSI and
OVSO pins. This requires 2 feedback resistors to control the output voltage as well as
an Rs resistor for the dynamically programmed output voltage. Connect the appropriate
resistors RF and RI (Table 1) from pin 6 SP6656 FB to Vout and to the GND.
For Vout Low, select OVSI = L and use the formula below to set the output voltage:
RF
=
 ^Vout
 ^0.8
−
1

•
RI
For Vout High, select OVSI = L, and the RS resistor will be switched in to change the
output voltage from the previously set voltage to a larger output voltage, determined by
the following equation:
RF
=
 ^Vout
 ^0.8
−1
•
RA
RI * RS
where RA =
RI + RS
Table 1. SP6656EB BILL OF MATERIALS
Component
L1
CIN
COUT
RVIN
CVIN
RI
RF
RF
CF
Vo = 1.8V
10uH, Murata LQH32CN100K11, 0.3ohm, 0.45A, 1210
10uF, TDK C2012X5R0J106M, 0.005ohm, 6.3V, X5R, 0805
10uF, TDK C2012X5R0J106M, 0.005ohm, 6.3V, X5R, 0805
10 Ohm 5%, 0603
1uF, TDK C1608X5R0J105M, 0.03ohm, .3V, X5R, 0603
200k 1%, 0603
249k 1%, 0603
200k 1%, 0603
22pF ceramic, 0603
Rev 10/17/05
2
SP6655 Evaluation Board Manual